China's RATA Introduces 1,800 kW Medium-Voltage Containerized Load Bank

Deyang Rata Technology Co., Ltd. introduces a 10.5 kV load testing system designed for gas-engine power plants, generator testing and electrical infrastructure applications.

Deyang Rata Technology Co., Ltd. has introduced its RATA-1800KW 10.5kV Containerized Resistive AC Load Bank, a medium-voltage power testing system developed for gas-engine power plants and other electrical infrastructure applications. The system is designed to absorb surplus active power during sudden load rejection in island-mode power generation, while also supporting controlled load testing of generators, transformers, uninterruptible power supply (UPS) systems, and related electrical equipment.

The 1,800 kW load bank operates at a power factor of 1.0 and incorporates a 10.5 kV main circuit with a dedicated transformer that steps down the voltage to 0.4 kV on the load side. Its configuration is intended to support installations requiring medium-voltage connections and controlled management of electrical loads.

Supporting Power Plant Stability and Equipment Testing

In island-mode operation, gas-engine power plants operate independently of the main electricity grid. Sudden reductions in connected demand can create excess generated power and affect generator frequency. The RATA-1800KW is designed to absorb this surplus active power, helping maintain frequency and support system stability during load rejection events.

Beyond this application, the equipment can perform rated-load testing, step-loading, transient-response testing and overload testing. These functions provide power plant operators, equipment manufacturers and maintenance teams with a controlled method of evaluating electrical equipment under different operating conditions.

The system is configured with 21 load stages, including a minimum adjustment step of 1 kW. This arrangement allows operators to apply incremental loads and conduct testing across different power levels up to its rated capacity of 1,800 kW.

Hybrid Switching and Electrical Design

The RATA-1800KW combines contactor and thyristor switching technologies. Its contactors are designed to close within 35 milliseconds and open within 75 milliseconds, while the thyristor switches provide switching response within 20 milliseconds. The hybrid arrangement supports steady-state loading alongside faster responses during transient testing.

The resistor assemblies use AISI 304 stainless-steel finned tubes, nickel-chromium NiCr 6023 resistance wire and Sg-9 magnesium oxide insulation. According to the technical specifications, individual resistor elements undergo a 3,000 V DC withstand test for one minute, while series-connected assemblies achieve a dielectric strength of 20 kV.

The resistor design accommodates temperatures of up to 1,300°C, with average fin temperatures maintained at or below 300°C. Measurement accuracy is specified at ±0.5% for voltage, current, power and power factor, and ±0.1% for frequency.

Containerized Configuration and Control Systems

The equipment is housed in a container measuring 6,000 × 2,400 × 2,600 mm and is rated IP54 for outdoor installation. Its vertical airflow arrangement draws air through lower intake openings and releases heated air through a roof-mounted exhaust chimney. The specified operating temperature range is -27°C to +48°C, with an installation altitude below 2,500 meters.

For field integration, the system incorporates a 12 kV vacuum circuit breaker and an S11-M-2500/10.5/0.4 step-down transformer. This configuration enables connection to a 10.5 kV medium-voltage busbar through an integrated arrangement, reducing the need for separate external switching and transformer equipment.

Operators can manage the load bank through a local HMI touchscreen displaying voltage, current, power and frequency measurements. Remote operation is supported through Nexus-1 PC software using Modbus TCP or Modbus RTU over RS485. The system also supports plant master control panel (MCP) integration through dry contacts and 4–20 mA analogue control signals.

Protection functions include high-temperature and low-airflow alarms, thermal emergency cut-off, smoke detection, over-voltage protection and an emergency stop mechanism.

Manufacturing, Testing and Service Support

Production involves engineering design, resistor manufacturing, switching assembly, container modification and system integration. Before delivery, the complete unit undergoes dielectric withstand testing, individual verification of all 21 load stages, full-load temperature-rise testing and protection interlock checks. Factory documentation includes a test report, operation and maintenance manual, and electrical schematics.

The equipment has a specified design life of 30 years and a service life of 15 years. Its listed warranty period is 24 months after delivery. The company also describes lifecycle support arrangements that include spare parts availability, technical assistance and remote operation and maintenance services.

About Deyang Rata Technology Co., Ltd.

Founded in 2013, Deyang Rata Technology Co., Ltd. is a professional resistive load bank manufacturer specializing in the research, development, and manufacturing of low- and high-voltage load banks and power testing systems.

The company holds ISO 9001:2015, ISO 14001:2015 and ISO 45001:2018 certifications and serves customers across power generation, marine and offshore, data center, renewable energy, energy storage and aerospace sectors. It reports serving more than 200 customers worldwide.